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Is 5G Fixed Wireless Access for Broadband Too Good to Be True or Too Good to Pass Up?

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by Barry Manz, Editor, Microwave Product Digest

Fixed wireless access (FWA) is getting a lot of media attention these days, as carriers like Verizon and T-Mobile are rolling out 5G FWA service as a replacement for fiber and hybrid fiber coax (HFC) to deliver high-speed broadband to consumers. Although it’s just a little over a year old, it’s becoming a huge success, so much so that both carriers are pleading with the FCC to get more spectrum to support it. A report from Ericsson recently illustrates projected growth though 2028 (Figure 1).

In fact, the broadband industry’s growth came almost entirely from FWA last year, according to T-Mobile’s 2022 State of Fixed Wireless report. These are impressive numbers, and what’s partly driving this growth is an almost universal loathing of cable companies that have for years ranked dead last in customer satisfaction. In short, people are looking for alternatives to cable, and where 5G FWA is available, they’re signing up (Figure 1).

Figure 1: Predicted number of FWA subscribers using either 4G or 5G Source: Ericsson

That’s not to say that cable (i.e., “linear”) TV is going away anytime soon, even as the number of traditional pay-TV customers continues to decline to about 60 million today. As this trend continues, it becomes unprofitable for cable companies to support the hundreds of channels they provide. Some, including Frontier, are simply abandoning this approach and offering streaming as an alternative, in most cases YouTube TV or Hulu + Pay TV, which like cable, provide hundreds of channels. Rather than continuing to invest in linear programming, they outsource their previous offerings and concentrate on providing broadband with the option to bundle it with mobile, thus becoming mobile virtual network operators (MVNOs) that lease service from wireless carriers.

This isn’t a decision cable companies take lightly. Most of their revenue still comes from big budget advertisers that want to reach the most subscribers and are less interested in targeting specific audiences provided by streaming services. For example, Nielsen reports that 68% of total TV time was spent last year with linear TV while 32% viewed only streaming services.

FWA Defined

FWA systems typically consist of a base station connected to a fixed network and several subscriber units spread out over a specific area. The base station then sends microwave, or millimeter-wave signals to communicate with the subscriber units, allowing consumers to connect to the fixed network and access high-speed data services. These transmitters are attached to stationary structures such as poles, buildings, or towers. Systems using mid-band frequencies deliver lower speeds because they have less available bandwidth, while millimeter-wave systems aren’t limited in this way (Figure 2).

Figure 2: The speed of FWA systems depends on the frequencies they use Source: Anritsu

There are six main reasons FWA is gaining momentum in the industry. Network performance keeps improving, making FWA increasingly competitive and good enough for various use cases, including extensive video streaming. In addition, new spectrum in several bands is being made available globally. At the same time, the network cost per delivered bit keeps dropping, enabling a viable operator business case for FWA, and making it affordable to households for services such as streaming.

FWA deployments have three main advantages over fiber deployments, related to time to market, financial investment profile, and re-use of mobile infrastructure. FWA has a shorter time to market than fiber and leverages existing mobile network infrastructure, utilizing spare capacity and already acquired but undeployed spectrum. Once that capacity is utilized, new capacity can be added to existing sites, either through software upgrades or additional new hardware, so there is no immediate need to build new sites.

Conversely, building out fiber is a much longer process, requiring permits and civil works to dig up the ground. FWA deployment on customer premises is also typically faster than fiber deployment. Fiber always requires home activation at the customer location, while FWA can usually be deployed through self-installation.

FWA also has a more attractive investment and risk profile than fiber. Fiber build-out is a capital intensive process, with most of the investment made up front (that is, before signing up customers and earning revenues). At the same time, the investment returns diminish as fiber deployments move away from dense urban areas and fewer homes are served per kilometer of fiber. According to Broadband Communities Magazine, the cost per home connected for rural homes is 2.5 times higher for fiber compared to FWA, where 30% of households subscribe. 

FWA has a lighter investment profile, with lower initial investment (if any, when spare capacity is utilized) and investment scaling in line with subscriber growth. Moreover, capacity investments for FWA can be shared with other mobile network services, resulting in lower risk. Even if there is no uptake of FWA services, the operator can still use that capacity for other services.

Finally, FWA deployments reuse existing infrastructure including towers, with most upgrades performed without site visits unless new hardware is required. Conversely, fiber build-out is resource intensive, requiring construction, often with excavation and transportation of resources.

FWA has its Roots in WISPs

It’s important to remember that although 5G FWA is getting the most attention, another FWA solution has been available since 2003 from companies called Wireless Internet Service Providers (WISPs). Like 5G FWA, WISPs cover the last mile, primarily to rural areas where there is often no alternative, with performance that meets even the basic broadband requirements for bandwidth and speed. They can also provide telephone service via VoIP, act as Wi-Fi hotspots, provide backhaul, and recently have been exploiting the growing need for IoT connectivity. WISPs range from very small companies with a few hundred subscribers to larger ones with several hundred thousand. To understand this industry, a little history is necessary.

In the late 1990s, “high-speed” Internet access was provided by DSL (if the customer was near enough to a central office switch) and, to a lesser degree, by cable. For everyone else, it was dial-up or nothing, which was almost always the case in rural areas. To remedy this, some technically savvy people in Wyoming decided to take the matters into their own hands, using Wi-Fi to provide Internet access to their homes and sometimes to their neighbors.

LARIAT, a non-profit rural telecommunications cooperative founded in 1992 in Laramie, WY, is often cited as the first WISP in the U.S., “going live” in 2003. LARIAT remains in operation today as LARIAT.NET, a “locally owned, locally-operated, locally-managed non-franchise operation” and still serves Laramie, with service plans that include speeds up to 1 Gb/s, conditions and the state of the network permitting.

Figure 3: A typical WISP antenna mounted on a customer’s house

As the news spread, more people in the area wanted in, and the pioneers found they were providing a service to the community rather than simply convenience for themselves, and so the WISP industry was created. LARIAT initially used WaveLAN equipment made by NCR Corp. that operated in the unlicensed 900 MHz Industrial Scientific and Medical (ISM) band. WaveLAN was conceived by Lucent Technologies to take advantage of the new IEEE 802.11 standard and could deliver downlink speeds of about 1.1 Mb/s over a distance of about 70 ft. A typical residential WISP antenna is shown in Figure 3.

DOCSIS 4.0: Just in Time or Too Late?

It’s a safe bet that by the end of the decade, traditional cable TV as we know it will have all but disappeared, although what’s in store is anyone’s guess, as streaming changes by the week. Ironically, this is happening just as the latest cable standard, DOCSIS 4.0, is being introduced which, as a full-duplex technology, allows HFC to overcome its most significant disadvantage compared to fiber: the inability to deliver high speeds in both the downlink and uplink paths.

DOCSIS 4.0 supports downstream speeds up to 10 Gb/s and up to 6 Gbps in the upstream path, which makes it comparable to fiber and provides a roadmap toward applications like interactive video conferencing, gaming, and virtual reality that demand symmetric speeds along with very low latency. Before DOCSIS 4.0, cable was limited to the upstream capacity of 1.5 Gb/s, which is rarely achieved as most cable customers are more accustomed to upstream speeds of one-third of the downstream speed. Consumers have grudgingly accepted asymmetrical transmission because data consumption is typically only 10% of their downstream consumption. That’s no longer unacceptable; without DOCSIS 4.0, HFC would likely fade into history.

So, with the arrival of 5G FWA and cable finally catching up to fiber, consumers now have three choices, HFC, fiber, and FWA, not all of which are widely available. However, to be competitive, FWA has to deliver blazingly fast speeds in both directions, and fiber is currently the only technology that provides the virtually unlimited bandwidth required to achieve it.

Consequently, the race is on to deploy massive quantities of fiber in as many places as possible as quickly as it can be planted. For fiber, the major challenge, especially in unserved and underserved areas, is that it can be costly to deploy as it requires securing permissions, digging trenches (Figure 4), laying out the last mile, and deploying technician-installed equipment at households and businesses.

Figure 4: Laying fiber is extremely expensive and faces various challenges, from permitting to the construction or reconstruction of the sites where the trenches are dug

While 5G FWA requires a broad bandwidth source at its input, the same is true for its output, translating into the need for a considerable spectrum of which little is available at microwave frequencies. As a result, providers use millimeter-wave frequencies specified within the 3GPP 5G standards allocated by the FCC in the U.S. and similar agencies in other countries.

Verizon’s 5G Home Internet operates at 28 and 29 GHz, and T-Mobile’s 5G Home Internet operates at 24, 28, and 39 GHz as well as 2.5 GHz (the latter is a potential advantage thanks to its better propagation characteristics). AT&T has been playing its cards differently, as the company has been rolling out massive amounts of fiber throughout the U.S., with far less emphasis on FWA than its competitors. As a result, it’s been the last to enter the FWA market, only formally announcing its Internet Air earlier this year and offering it primarily to rural customers. Speeds are well below those of the others.

At millimeter wavelengths, 5G FWA can provide service comparable to fiber and can use active phased array antenna technology to steer narrow beams of energy in multiple directions. These narrow beams also enable a higher density of users without causing interference. The primary disadvantage is extreme attenuation from almost anything from foliage to precipitation and building materials, including the low-emissivity (low-E) glass used in modern homes and buildings.

Propagation at these frequencies is very short and line of sight, which limits range to a few hundred feet under ideal conditions. However, enormous advances in semiconductor technology, AI, and cloud computing hold the keys to nearly eliminating the challenges that have previously impeded efforts to exploit the vast potential of the millimeter-wave region.

Making Millimeter-wave FWA Work

To understand how this has become possible, remember that some fiber is available in all but the most remote areas, if only to a few locations in the community. From only a single point of access, the fiber can connect to a millimeter-wave transceiver and its associated antennas mounted on the roof of the building or another nearby structure. This is the approach taken by WeLink, which provides FWA services to customers in Las Vegas and Henderson, Nevada, and Phoenix, Tucson, and other parts of Arizona.

The transceiver connected to the fiber access point transmits these beams to one or two customers with receivers and antennas that are even smaller, allowing them to blend into their surroundings, a primary consideration for homeowners and businesses (Figure 5).

Figure 5: From the point where WeLink accesses fiber, the signals are transmitted at millimeter wavelengths via narrow beams to specific locations, eliminating further use of fiber or any other wired medium Source: WeLink

As these subsystems can also retransmit the signal, they can send it to other users. The same process continues as one home or business connects to another and throughout the community. The signals captured by the receiver then enter the building via an Ethernet cable connected to an indoor Wi-Fi router, after which they are available to the usual array of connectable devices, from TVs to smartphones, PCs, laptops, and home automation products.

At millimeter-wave frequencies, antennas and the radios themselves become very small, making it possible, for instance, to build a transceiver and integrated active phase-array antenna with 64 electronically steerable antenna elements in a footprint about the size of a paperback book. These antennas are active, meaning that multiple signals or beams can be steered to specific locations, in this case, to end-users. As the beams are very narrow, the likelihood of interference is very low.

There are big advantages to this approach. There is no need to run fiber to every customer location because the repeater connected to the fiber can serve dozens of customers wirelessly at gigabit-per-second speeds. Millimeter-wave networks do not rely on fiber beyond their single point of access. This means that FWA used in this mesh-network-based approach is much less expensive, so monthly costs can be a fraction of those typically provided by fiber-to-the-home.

FWA in the Future

A few years ago, using millimeter-wave frequencies for FWA was very expensive and used primarily by utilities and the telecommunications industry for point-to-point relays from tower to tower or mountain to mountain. However, the dramatic reduction in cost afforded by technological advances has dramatically reduced these costs by orders of magnitude, and the result is a rapid increase in growth that will continue for many years.

However, it’s not likely to replace fiber and HFC everywhere, at least in the foreseeable future, as HFC has been massively deployed and will soon have the benefit of full duplex capability, and while fiber is not as well entrenched as HFC, AT&T and other companies are rapidly rolling it out in currently unserved places. That said, 5G FWA is comparatively new, so it’s too soon to form any consensus about its reliability or how fast it may become. What is certain is that it is indeed coming because its installation is nearly painless (no wires or cable boxes), and carriers can dramatically reduce costs because no truck roll is required to install it.

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